Mobile computing devices have been developed to increase the functionality that is made available to users in a mobile setting. For example, a user may interact with a mobile phone, tablet computer, or other mobile computing device to check email, surf the web, write texts, interact with applications, and so on. Designing devices with a mobile form factor, however, presents a number of challenges.
For instance, a typical mobile device may operate under battery power (e.g., in a mobile scenario) and may also operate when connected to an external power source, such as an alternating current (AC) socket. Since mobile devices typically operate under direct current (DC) power, AC power from an external power source is usually converted to lower-voltage DC power prior to be supplied to internal components of a mobile device. However, during conversion of AC to DC for mobile device power needs, common mode noise (e.g., from the power supply switching circuit for converting high voltage to low voltage DC) may be coupled into the lower voltage DC output to the mobile device, which can cause touch malfunction in a touch-enabled mobile device.